Pass-through structures have been known heretofore wherein objects could be transferred from one area to another, or from one room to another through a dividing wall. However, they were not suitable for passing through objects such as X-Ray film cassettes, where certain precautions were necessary. For example, unexposed X-ray film requires lead-lined protection when being transferred.
Furthermore, in the pass-through structures heretofore known, there was no way to prevent a person on one side of such a dividing wall from rotating the inner drum inadvertantly or prematurely before exposed film might have been placed within the structure.
The present structure is designed with features which make it particularly applicable for use in transferring X-ray film cassettes from one area to another, although its usefulness is not necessarily limited to that purpose. It is considered that the lead-lining of one or both drums and the latch means are essential for the purposes of this invention. Other improvements have been made, as will appear more fully hereinafter.